The knee joint is frequently the object of injury and is often repaired using arthroscopic surgical procedures. An example of such arthroscopic surgical procedure is the replacement of anterior cruciate ligaments of the knee. The tearing of these ligaments is common in sports activities such as football or skiing.
Various natural and synthetic tissue replacements are used. The replacements can be xenograft, allograft or autograft. For example, fascia lata soft tissue replacements are flexible strands which are affixed to a threaded stud and turned into the femoral tunnel. Hamstring soft tissue replacements are also currently fixed over a screw in the tibial tunnel and fixed on the lateral femur. This technique requires the femoral tunnel to completely penetrate the femur. In addition, according to present procedures, fixation of the soft tissue replacement on the femoral side requires a large incision.
Further, various other graft portions, such as a patellar tendon graft, which can include a bone tendon bone graft can be used. The graft can be harvested from between patella and the selected bone to which the tendon is anchored. This allows for creation of a bone-tendon-bone graft where the tendon is already anchored to bone portions and only the bone portions are fixed relative to the implant site in the bone. Further examples include a quadriceps tendon graft as various examples of autografts. All grafts from similar sites of selected individuals can also be used in a patient requiring a graft. Further, xenograft materials can be harvested from compatible animals for implantation to selected patients. Also, synthetic materials, such as those that are biologically compatible and include appropriate physical properties can be used. One skilled in the art is generally aware of the various types of graft materials that can be provided for performing a grafting procedure.
It has been difficult to insert and fasten a soft tissue replacement in a blind hole or tunnel. Attempts have been made to thread the soft tissue replacement through the tunnel and over an anchor, but with some difficulty. Thus far, the prior art has not developed a quick and efficient way to implant a soft tissue replacement over an implanted anchoring system.
While offering certain improvements in arthroscopic surgery to repair ligaments, the prior art may still be improved upon to overcome the limitations on the endoscopic hamstring soft tissue replacement fixation due, in many instances, to the weakness of the flexible strand used to span the gap between the tendon soft tissue replacement and the fixation post.
Other techniques attempt to use biological fixation to augment or replace mechanical fixation. While increasing fixation strength these techniques require time to fully realize their fixation potential. Additionally the techniques may take additional surgical time and resources that a purely mechanical fixation technique may not require.